(e) List concisely the user requirements that led to this ER schema design.(f) Suppose that every customer must have at least one account but is restrictedto at most two loans at a time, and that a bank branch cannot have more than1000 loans. How does this show up on the (min,max) constraints?Answer:(a) Entity types: BANK, ACCOUNT, CUSTOMER, LOAN(b) Weak entity type: BANK-BRANCH. Partial key: BranchNo.Identifying relationship: BRANCHES.(c) The partial key BranchNo in BANK-BRANCH specifies that the same BranchNo valuemay occur under different BANKs. The identifying relationship BRANCHES specifies thatBranchNo values are uniquely assigned for those BANK-BRANCH entities that are relatedto the same BANK entity. Hence, the combination of BANK Code and BranchNo togetherconstitute a full identifier for a BANK-BRANCH.7

(d) Relationship Types: BRANCHES, ACCTS, LOANS, A-C, L-C. The (min, max) constraintsare shown below.(e) The requirements may be stated as follows: Each BANK has a unique Code, as well as aName and Address. Each BANK is related to one or more BANK-BRANCHes, and theBranhNo is unique among each set of BANK-BRANCHes that are related to the same BANK.Each BANK-BRANCH has an Address. Each BANK-BRANCH has zero or more LOANS andzero or more ACCTS. Each ACCOUNT has an AcctNo (unique), Balance, and Type and isrelated to exactly one BANK-BRANCH and to at least one CUSTOMER. Each LOAN has aLoanNo (unique), Amount, and Type and is related to exactly one BANK-BRANCH and to atleast one CUSTOMER. Each CUSTOMER has an SSN (unique), Name, Phone, andAddress, and is related to zero or more ACCOUNTs and to zero or more LOANs.(f) The (min, max) constraints would be changed as follows:3.24 Consider the ER diagram in Figure 3.19. Assume that an employee may work in up to two departments or may not be assigned o any department. Assume that each department must have one and may have up to three phone numbers. Supply (min, max) constraints on this diagram. State clearly any additional assumptions you make. Under what conditions would the relationship HAS_PHONE be redundant in this example?Answer:Assuming the following additional assumptions:- Each department can have anywhere between 1 and 10 employees.- Each phone is used by one, and only one, department.- Each phone is assigned to at least one, and may be assigned to up to 10 employees.- Each employee is assigned at least one, but no more than 6 phones.The resulting ER Diagram will have the (min, max) constraints shown in Figure A.Relationship HAS-PHONE would be redundant under the following conditions:- Each employee is assigned all of the phones of each department that he/she works in.- An employee cannot have any other phones outside the departments he/she works is.EMPLOYEE8

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PHONEDEPARTMENTHAS-PHONE CONTAINSWORKS-IN(0, 2)(1, 3)(1, 10)(1, 10) (1, 1)(1, 6)3.25. Consider the ER diagram in Figure 3.20. Assume that a course may or may not use a textbook, but that a text by definition is a book that is used in some course. A course may not use more than five books. Instructors teach from two to four courses. Supply (min, max) constraints on this diagram. State clearly any additional assumptions you

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